The Aspire One is a really nice pc. (Typing on it now)
I looked at one today, single 1.6 Ghz Intel Atom Processor, 1 gig of RAM, 120 GB hard drive, ethernet, 3 usb ports, audio in, audio out, a couple of mini ports for cameras/video, traditional VGA out port, Windows XP, a couple of browsers, word pad, MS Office trial, and some other bundled software full versions or trials. $349.00 dollars.
When I saw this it was not bad, but an external super drive would cost $99 dollars from 3rd party maker. I think 2.2 to 2.5 pounds with 9" inch LCD.
Though I use my iBook for word processing/school and mini Mac for internet/e-mail, I would consider another Mac but there's no reason since I don't do games or Adobe/Macromedia suites/digital video.
I think this particular Acer, as opposed to the Eee PC or the semi-compact 4 lb. models, isn't a bad machine for basic internet/e-mail/word processing/solitaire/light games/photoshop elements/MS Office. I so wish it were a Mac, even at $499, but this Acer looks like a real winner all the way around.